xref: /linux/arch/arm/include/asm/insn.h (revision 3d0fe49454652117522f60bfbefb978ba0e5300b)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_ARM_INSN_H
3 #define __ASM_ARM_INSN_H
4 
5 #include <linux/types.h>
6 
7 /*
8  * Avoid a literal load by emitting a sequence of ADD/LDR instructions with the
9  * appropriate relocations. The combined sequence has a range of -/+ 256 MiB,
10  * which should be sufficient for the core kernel as well as modules loaded
11  * into the module region. (Not supported by LLD before release 14)
12  */
13 #define LOAD_SYM_ARMV6(reg, sym)					\
14 	"	.globl	" #sym "				\n\t"	\
15 	"	.reloc	10f, R_ARM_ALU_PC_G0_NC, " #sym "	\n\t"	\
16 	"	.reloc	11f, R_ARM_ALU_PC_G1_NC, " #sym "	\n\t"	\
17 	"	.reloc	12f, R_ARM_LDR_PC_G2, " #sym "		\n\t"	\
18 	"10:	sub	" #reg ", pc, #8			\n\t"	\
19 	"11:	sub	" #reg ", " #reg ", #4			\n\t"	\
20 	"12:	ldr	" #reg ", [" #reg ", #0]		\n\t"
21 
22 static inline unsigned long
23 arm_gen_nop(void)
24 {
25 #ifdef CONFIG_THUMB2_KERNEL
26 	return 0xf3af8000; /* nop.w */
27 #else
28 	return 0xe1a00000; /* mov r0, r0 */
29 #endif
30 }
31 
32 unsigned long
33 __arm_gen_branch(unsigned long pc, unsigned long addr, bool link, bool warn);
34 
35 static inline unsigned long
36 arm_gen_branch(unsigned long pc, unsigned long addr)
37 {
38 	return __arm_gen_branch(pc, addr, false, true);
39 }
40 
41 static inline unsigned long
42 arm_gen_branch_link(unsigned long pc, unsigned long addr, bool warn)
43 {
44 	return __arm_gen_branch(pc, addr, true, warn);
45 }
46 
47 #endif
48